1. features

As we all know, the switch plays an important role in transmitting the instruction information in the whole electronic equipment. There are many kinds of switches, and their development has been continuously updated with the progress of electronic products. In 1950s to components of the toggle switch, toggle switch, the switch is dominant; 60s to a key switch combination switch as the representative, to complete a simple conversion function; with the increase of application expansion and the function of the 70s and the emergence of conductive rubber keyboard switch, and the switch is in a film a new electronic device at the end of 70s early 80s research and development, which is in accordance with the electronic product to the miniaturization, digitization, intelligent, multi-functional product development needs.

The film is made of a printed circuit switch switch contacts with the conductive paste in flexible polycarbonate or polyester film, is a contact switch.

The film switch is a plane type, multilayer combination and sealed structure, and is an assembly of an electronic whole control system, which is provided with a button switch, a panel function mark, a reading display transparent window, an indicator lamp, a window hole and a circuit.

It has the following characteristics:

(1) durability

The life of the membrane switch can generally reach more than one million times. The reason why it has such a long life is that the action of the switch is realized only by the vertical direction of the elastic film. The elastic film even after millions of times but due to creep, the creep rate is small, only 0.1~0.3mm (both switch trip), and the reasonable selection of materials, far did not reach the yield limit of the film, so the film material can withstand more than one million times the life without deformation. On the other hand, the switch contacts

Is the vertical contact, wear is very small; and the screen printing contact can form a sufficient thickness and silver contacts in printing a layer of conductive carbon, in order to achieve the purpose of high wear resistance, self lubrication, so the thin film switch life, than the mechanical contact switch to increase the number of times above.

(2) good sealing performance

Because the membrane switch is an integral sealing structure, the switch contacts are free from harmful gas and are not easy to oxidize. The utility model has the characteristics of waterproof and dustproof, thereby being more suitable for various abominable environments.

(3) small in size, light in quality and reliable in structure

In the design of membrane switch can be assembled into film keyboard, the density, and it is the seal sheet type structure is composed of multilayer films formed by combining all connections between the switches and the lead wire is composed of screen printing once completed, the total thickness in 1~3mm, therefore reduces the volume, reduce the weight, improve reliability.

(4) rich in color and beautiful in appearance

The film switch can be individualized according to the design concept of the user, and the design of the color pattern reflects the individuality, and the decorative effect reflects the comprehensive characteristics of the material beauty, the decorative beauty and the technological beauty.

(5) reduce the matching costs of mechanical and electrical products

The traditional mechanical switch needs welding when it is installed, even with the fixed support. While the thin film switch installation for paste type, as long as you can remove gummed paper, firmly stuck on the surface of the wire socket on the rear exit insert machine circuit, can instantly switch on the circuit. It saves labor and materials and reduces the supporting cost of the whole machine.

2. applications

A membrane switch is a non self locking switch. Apply to switch power less than 1W ah, the maximum operating voltage: 42V (DC) or 25V (DC), the maximum operating current is less than 100 mA working occasions. The utility model can be widely applied to all microcomputers and numerical control. Intelligent instruments, meters and many fields of electronic circuits with discrimination and memory function.